The Duke and Duchess of Cambridge announced their pregnancy early amid
concerns that it would become public on Twitter and the internet.

By Steven Swinford, Gordon Rayner and Sam Marsden

9:00PM GMT 03 Dec 2012

The Duchess, who is less than 12 weeks pregnant, decided to make news of her pregnancy public after she was taken to hospital because she was suffering from a severe form of morning sickness.

A royal source confirmed that the couple were concerned that news of their pregnancy would leak out and be repeated on Twitter and other social-networking websites.

Their decision comes amid growing concern that the internet appears beyond the reach of regulation. Lord Justice Leveson concluded it was an “ethical vacuum” which the press should seek to rise above.

The Duchess's pregnancy has been the subject of fevered speculation on the internet ever since the couple married. The British press, by contrast, did not repeat the rumours out of respect for the couple's privacy.

John Whittingdale, Conservative chairman of the culture, media and sport select committee, said: "I'm pleased that the press showed restraint in reporting the rumours.

"We live in an age where the internet is becoming more prevalent and it is very difficult to enforce the same standards on websites, many of which are not even in this country."

Last week, during a visit to Cambridge, the Duke was given a baby-grow which he accepted, saying “I’ll keep that.”

Hundreds of people subsequently took to Twitter and the internet to comment on pictures of the Duchess and repeat rumours that she was pregnant.

"There has been far too much stomach holding and floaty dresses the past week," one person said. Another tweeted: "Kate Middleton is pregnant... [in] latest pics her face is glowing and hair looks thicker".

The comments were fuelled by magazines in the US and Australia, which reported claims from friends that she was pregnant.

One newspaper in Canada went as far as publishing a top 10 list of reasons why the Duchess was pregnant.

They included the fact she had been seen "sipping water instead of champagne at official events", and claims her "bangin's new hairdo" was intended to draw attention away from her "growing tummy".

The royal source said: "Considerations about Twitter and the Internet formed part of the decision in going public, as it shapes all decisions about the handling of the media in the current age."

Lord Justice Leveson devoted just 12 pages of the 1,987 page report to discussing the role of the internet, and concluded that online news outlets could subscribe to regulation if they wished.

He said that while people will not assume that what they read on the internet is “trustworthy”, they expect newspapers to be a “quality product”.

He said: “Some have called it a 'wild west’ but I would prefer to use the term 'ethical vacuum’. The internet does not claim to operate by express ethical standards, so that bloggers and others may, if they choose, act with impunity."

However Niri Shan, head of media law at London-based firm Taylor Wessing, said: "One of the big criticisms of Leveson is that while he is talking about the regulation of the mainstream media, he doesn't believe that social media is influential in any way.

"But we all know that because of the viral nature of social media, you can have a circulation that far exceeds anything in a national newspaper, either online or in print.

"It does put our media at a competitive disadvantage, and it does bring into stark focus the contrasts in the regulatory systems and law when anyone going on the internet can read this stuff."

He added: "When it comes to particularly the relationship with the Royal family, the British press are pretty responsible."